Soft tissue implants are commonly used for a wide variety of clinical and cosmetic purposes. One use involves reconstructive applications that rebuild and restore a body part or structure to correct deformities from congenital anomalies, trauma, cancer, infections, disease, or medication side effects. The soft tissue implant serves to replace lost tissue, provide aesthetic improvement, support surrounding tissue and/or to maintain the normal appearance of the body. The restoration of a normal appearance has a significant beneficial psychological effect on post-operative patients, alleviating much of the shock and depression that often follows extensive surgical procedures. Another use involves augmentation applications that alter a body part or structure usually to improve its cosmetic or aesthetic appearance. Augmentation of the appearance also has beneficial psychological effects that improve self-esteem, well-being, and confidence of an individual.
The use of implantable prosthesis for breast shaping, for example, for breast reconstruction following traumatic or surgical loss of breast tissue or, electively to increase volume of the breast is well known. Typically, the prosthesis or implant comprises of a soft, flexible envelope containing a liquid or gelatinous material. The envelope is commonly made from silicone or other bio-compatible polymer with varying degrees of elastic memory and permeability. These prostheses are filled with saline, and silicone oil or gel to mimic the tone and feel of natural breast tissue.
Capsular contracture is an adverse event related to breast implant surgery. It is believed to be a result of the immune system response to the presence of a foreign material in the body. A normal response of the body to the presence of a newly implanted object, for example a breast implant, is to form periprosthetic tissue, sometimes in the form of a capsule containing collagen fibers around the implant. Capsular contracture occurs when the capsule begins to contract and constrict the implant. This contracture can be discomforting or even extremely painful, and can cause distortion of the appearance of the augmented or reconstructed breast.
The exact cause of contracture is not known. However, some factors that may influence contracture include bacterial contamination of the implant prior to placement, submuscular versus subgladular placement, and smooth surface implants versus textured surface implants, the type or degree of texture on the implant surface, and bleeding or trauma to the area.
Surface texturing has been shown to reduce capsular contracture when implants are placed in the subglandular position compared to what are known as “smooth” surface implants. In other words, it is generally well known in the art that patients fitted with textured implants are less likely to exhibit contracture, relative to patients fitted with non-textured or smooth surface implants placed subglandularly. However, there is still a need for a textured implant that is specifically designed to encourage optimal tissue integration in the most beneficial location, and potentially reduce capsule formation and collagen fiber alignment described herein.
Conventional manufacturing processes for textured implants include the application of dissolvable particles onto a tacky elastomeric surface of an implant shell and subsequent removal thereof, leaving a dimpled or textured surface in the elastomer. Alternating layers of particles and elastomer provide a way to produce a textured surface defined by a porous surface having a desired depth.
There remains a need for better devices and methods for texturing outer surfaces of breast implants.